In the state of the art applications, registration of unauthorized radios to the system is prevented by means of authentication methods. With this method, resource allocation is not made for the requests made by a radio that is not registered in the system.
In the state of the art applications, in a conventional system, the voice packets transmitted by a valid and authenticated radio in uplink can be listened to and the related parameters (LC, ES) in this valid packet can be obtained. These parameters can be programmed to a radio that is not registered in the system. When the foreign radio is enabled to start transmitting voice in the system frequency, the foreign radio both occupies the system and can engage in unauthorized communication via the system.
The International patent application document no. WO0124560, an application in the state of the art, discloses an encryption technique applied in the communication of the mobile device with the base station. This encryption process is performed by an encryption key and it is stated that the parameters compared in the encryption process are changed periodically.
The United States Patent document no. US2011314287, an application known in the state of the art, discloses a method which enables authentication between devices. It is disclosed that in this method, authentication is performed by matching the information of the device defined as the subscriber with the network information.
The United States Patent document no. US20120159588, an application known in the state of the art, discloses an authentication system which can also be applied in radio systems and allows access to a plurality of services through a single device. It is also disclosed that this system is periodically updated.
The United States Patent document no. US2011029770, an application known in the state of the art, discloses a radio communication system which enables to select the suitable process for authentication for the same user.